Security information and event management

ABSTRACT

Systems and methods are described for conducting work flows by an SIEM device to carry out a complex task automatically. According to one embodiment, an SIEM device may create a work flow that includes multiple security tasks that are performed by one or more security devices. When a security event is captured or the work flow is scheduled to be executed, the SIEM device starts the work flow by scheduling the security tasks defined in the work flow. The SIEM device then collects results of security tasks performed by the one or more security devices.

COPYRIGHT NOTICE

Contained herein is material that is subject to copyright protection.The copyright owner has no objection to the facsimile reproduction ofthe patent disclosure by any person as it appears in the Patent andTrademark Office patent files or records, but otherwise reserves allrights to the copyright whatsoever. Copyright© 2014, Fortinet, Inc.

BACKGROUND

1. Field

Embodiments of the present invention generally relate to the field ofnetwork security techniques. In particular, various embodiments relateto work flow processing for a security information and event management(SIEM) system.

2. Description of the Related Art

A large computer network may comprise hundreds of client computers,servers and other network devices that may be located at differentplaces. Multiple security devices, including, but not limited tofirewalls, antivirus devices, Intrusion Prevention System (IPS) devicesor Unified Threat Management (UTM) devices, can be deployed to regulatenetwork access and protect the network from attacks. The securitydevices may conduct various tasks to find vulnerabilities of thenetwork, regulate network access and protect the network from attacks.AN SIEM device may be deployed to collect results of the tasks performedby the security devices. The SIEM device may send out an alarm messageto the administrator when a high risk event is identified. The SIEMdevice may also generate a report to show the status of the network,such as the number, targets and sources of attacks that have beencaptured within a certain period. However, tasks that can be conductedby security devices of the network are independent and results of suchtasks cannot be transferred to another task. Furthermore, tasksconducted by different security devices may require differentparameters. Even the same task may require different parameters when itis conducted by security devices from different manufacturers. Thus,there is a need for improved SIEM devices that may schedule multipletasks of various security devices to automatically achieve comprehensivemanagement.

SUMMARY

Systems and methods are described for conducting work flows by an SIEMdevice to carry out a complex task automatically. According to oneembodiment, an SIEM device may create a work flow that includes multiplesecurity tasks that are performed by one or more security devices. Whena security event is captured or the work flow is scheduled to beexecuted, the SIEM device starts the work flow by scheduling thesecurity tasks defined in the work flow. The SIEM device then collectsresults of the security tasks performed by the one or more securitydevices.

Other features of embodiments of the present invention will be apparentfrom the accompanying drawings and from the detailed description thatfollows.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention are illustrated by way of example,and not by way of limitation, in the figures of the accompanyingdrawings and in which like reference numerals refer to similar elementsand in which:

FIG. 1 illustrates an exemplary network architecture in accordance withan embodiment of the present invention.

FIG. 2 illustrates exemplary functional units of an SIEM device inaccordance with an embodiment of the present invention.

FIG. 3 is a flow diagram for conducting a work flow in accordance withan embodiment of the present invention.

FIG. 4 is a flow diagram for scheduling tasks based on a special workflow in accordance with an embodiment of the present invention.

FIG. 5 is a flow diagram for scheduling tasks based on a work flowtemplate in accordance with an embodiment of the present invention.

FIG. 6 is a flow diagram for scheduling tasks based on a work flowtemplate in accordance with another embodiment of the present invention.

FIG. 7 is a flow diagram illustrating a website discovery work flow inaccordance with an embodiment of the present invention.

FIG. 8 is a graphic representation of a website discovery work flow inaccordance with an embodiment of the present invention.

FIG. 9 is a flow diagram illustrating a closed-loop work flow for asecurity event in accordance with an embodiment of the presentinvention.

FIG. 10 is an exemplary computer system in which or with whichembodiments of the present invention may be utilized.

DETAILED DESCRIPTION

Systems and methods are described for conducting work flow by an SIEMdevice to carry out a complex task. For example, an SIEM device maycreate a work flow or work flow template for conducting a complexfunction that may be made up of multiple tasks that are executed bymultiple security devices. The tasks may be conducted automatically andthe results of previous tasks in the work flow may be transferred tosubsequent tasks. Further, logical conditions may be defined todetermine if a subsequent task in a work flow should be conducted basedon the logical conditions. According to one embodiment, an SIEM devicemay create a work flow that includes multiple security tasks that areperformed by one or more security devices. When a security event iscaptured or the work flow is scheduled to be executed, the SIEM devicestarts the work flow by scheduling the security tasks defined in thework flow. The SIEM device then collects results of the security tasksperformed by the one or more security devices.

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of embodiments of the presentinvention. It will be apparent, however, to one skilled in the art thatembodiments of the present invention may be practiced without some ofthese specific details. In other instances, well-known structures anddevices are shown in block diagram form.

Embodiments of the present invention include various steps, which willbe described below. The steps may be performed by hardware components ormay be embodied in machine-executable instructions, which may be used tocause a general-purpose or special-purpose processor programmed with theinstructions to perform the steps. Alternatively, the steps may beperformed by a combination of hardware, software, firmware and/or byhuman operators.

Embodiments of the present invention may be provided as a computerprogram product, which may include a machine-readable storage mediumtangibly embodying thereon instructions, which may be used to program acomputer (or other electronic devices) to perform a process. Themachine-readable medium may include, but is not limited to, fixed (hard)drives, magnetic tape, floppy diskettes, optical disks, compact discread-only memories (CD-ROMs), and magneto-optical disks, semiconductormemories, such as ROMs, PROMs, random access memories (RAMs),programmable read-only memories (PROMs), erasable PROMs (EPROMs),electrically erasable PROMs (EEPROMs), flash memory, magnetic or opticalcards, or other type of media/machine-readable medium suitable forstoring electronic instructions (e.g., computer programming code, suchas software or firmware). Moreover, embodiments of the present inventionmay also be downloaded as one or more computer program products, whereinthe program may be transferred from a remote computer to a requestingcomputer by way of data signals embodied in a carrier wave or otherpropagation medium via a communication link (e.g., a modem or networkconnection).

In various embodiments, the article(s) of manufacture (e.g., thecomputer program products) containing the computer programming code maybe used by executing the code directly from the machine-readable storagemedium or by copying the code from the machine-readable storage mediuminto another machine-readable storage medium (e.g., a hard disk, RAM,etc.) or by transmitting the code on a network for remote execution.Various methods described herein may be practiced by combining one ormore machine-readable storage media containing the code according to thepresent invention with appropriate standard computer hardware to executethe code contained therein. An apparatus for practicing variousembodiments of the present invention may involve one or more computers(or one or more processors within a single computer) and storage systemscontaining or having network access to computer program(s) coded inaccordance with various methods described herein, and the method stepsof the invention could be accomplished by modules, routines,subroutines, or subparts of a computer program product.

Notably, while embodiments of the present invention may be describedusing modular programming terminology, the code implementing variousembodiments of the present invention is not so limited. For example, thecode may reflect other programming paradigms and/or styles, including,but not limited to object-oriented programming (OOP), agent orientedprogramming, aspect-oriented programming, attribute-oriented programming(@OP), automatic programming, dataflow programming, declarativeprogramming, functional programming, event-driven programming, featureoriented programming, imperative programming, semantic-orientedprogramming, functional programming, genetic programming, logicprogramming, pattern matching programming and the like.

Terminology

Brief definitions of terms used throughout this application are givenbelow.

The phase “security device” generally refers to a hardware device orappliance configured to be coupled to a network and to provide one ormore of data privacy, protection, encryption and security. The networksecurity device can be a device providing one or more of the followingfeatures: network firewalling, Virtual Private Networking (VPN),antivirus, IPS, content filtering, data leak prevention, antispam,antispyware, logging, reputation-based protections, event correlation,network access control, vulnerability management, load balancing andtraffic shaping—that can be deployed individually as a point solution orin various combinations as a UTM solution. Non-limiting examples ofnetwork security devices include proxy servers, firewalls, VPNappliances, gateways, UTM appliances and the like.

The phrase “network appliance” generally refers to a specialized ordedicated device for use on a network in virtual or physical form. Somenetwork appliances are implemented as general-purpose computers withappropriate software configured for the particular functions to beprovided by the network appliance; others include custom hardware (e.g.,one or more custom Application Specific Integrated Circuits (ASICs)).Examples of functionality that may be provided by a network applianceinclude, but is not limited to, Layer 2/3 routing, content inspection,content filtering, firewall, traffic shaping, application control, Voiceover Internet Protocol (VoIP) support, VPN, Internet Protocol (IP)security (IPSec), Secure Sockets Layer (SSL), antivirus, intrusiondetection, intrusion prevention, Web content filtering, spywareprevention and anti-spam. Examples of network appliances include, butare not limited to, network gateways and network security appliances(e.g., FORTIGATE family of network security appliances and FORTICARRIERfamily of consolidated security appliances), messaging securityappliances (e.g., FORTIMAIL family of messaging security appliances),database security and/or compliance appliances (e.g., FORTIDB databasesecurity and compliance appliance), web application firewall appliances(e.g., FORTIWEB family of web application firewall appliances),application acceleration appliances, server load balancing appliances(e.g., FORTIBALANCER family of application delivery controllers),vulnerability management appliances (e.g., FORTISCAN family ofvulnerability management appliances), configuration, provisioning,update and/or management appliances (e.g., FORTIMANAGER family ofmanagement appliances), logging, analyzing and/or reporting appliances(e.g., FORTIANALYZER family of network security reporting appliances),bypass appliances (e.g., FORTIBRIDGE family of bypass appliances),Domain Name Server (DNS) appliances (e.g., FORTIDNS family of DNSappliances), wireless security appliances (e.g., FORTIWIFI family ofwireless security gateways), FORIDDOS, wireless access point appliances(e.g., FORTIAP wireless access points), switches (e.g., FORTISWITCHfamily of switches) and IP-PBX phone system appliances (e.g., FORTIVOICEfamily of IP-PBX phone systems).

The terms “connected” or “coupled” and related terms are used in anoperational sense and are not necessarily limited to a direct connectionor coupling. Thus, for example, two devices may be coupled directly, orvia one or more intermediary media or devices. As another example,devices may be coupled in such a way that information can be passedthere between, while not sharing any physical connection with oneanother. Based on the disclosure provided herein, one of ordinary skillin the art will appreciate a variety of ways in which connection orcoupling exists in accordance with the aforementioned definition.

If the specification states a component or feature “may”, “can”,“could”, or “might” be included or have a characteristic, thatparticular component or feature is not required to be included or havethe characteristic.

FIG. 1 illustrates an exemplary network architecture 100 in accordancewith an embodiment of the present invention. In the context of thepresent example, network architecture 100 comprises a headquartersnetwork 110 and multiple branch office networks 121, 122, 123 and 124.Headquarters network 110 and branch office networks 121, 122, 123 and124 are connected through internetworks, such as the Internet 130.Headquarters network 110 comprises multiple network appliances, such asa local server 111 a, a PC 111 b, a laptop 111 c and other computingdevices that are operatively coupled to each other through a Local AreaNetwork (LAN), wherein the LAN is then operatively coupled with afirewall 112 that enables access to Internet 130. Firewall 112 separatesthe external computing environment, represented by Internet 130, fromthe internal computing environment of headquarters network 110. Firewall112 may intercept communications between Internet 130 and networkappliances of headquarters network 110 and scan for malware, viruses orother high risk network accesses. The internal structures of branchoffice networks 121-124 are omitted as they may be the same as that ofheadquarters network 110.

In the current example, an SIEM device 113 is connected to headquartersnetwork 110. SIEM device 113 may schedule vulnerability scanner 114 ofheadquarters network 110 and other vulnerability scanners of branchoffice networks 121-124 to scan computing/networking devices of thenetworks for vulnerabilities. Vulnerability scanner 114 may be any kindof vulnerability management devices that may be used for identifying andmitigating vulnerabilities that exist in computers or other networkappliances. Further, SIEM device 113 may schedule other security devicesof networks to conduct other security tasks. These security devices mayinclude, but are not limited to, firewalls, intrusion detection systems(IDSs), Web application firewalls (WAFs), system or Web scanningdevices, Distributed Denial of Service (DDoS) mitigation appliances,anti-spam devices, anti-spam devices that protect the networks. Thesecurity tasks include scanning for newly added devices and/or newservices, configuring and/or conducting network policies for controllingaccesses to a network and/or scanning/cleaning virus/spam at computingdevices. These security devices may conduct the security tasks at one ormore network layers and record the results of the tasks in their logs.The logs may be sent to SIEM device 113 in real time or periodically bythese security devices.

Although in the present example, SIEM device 113 is located atheadquarters network 110, those of ordinary skill in the art willappreciate that SIEM device 113 may located within any of the networks110 or 121-124. It will also be appreciated by one skilled in the artthat SIEM device 113 may be a cloud-based SIEM device that schedulessecurity tasks and collects logs from the security devices of allinternal networks. SIEM device 113 analyzes the logs from differentsecurity devices and sends out an alarm to the administrator of SIEMdevice 113 when abnormal activity is detected. SIEM device 113 may alsoprovide a report to the administrator regarding the status of the wholenetwork, such as total number of attacks detected within a particulartime period and the distribution of sources and targets of the attacks.

SIEM devices are useful to the administrator of a large network, whichmay include hundreds of computing devices distributed among differentlocations. However, existing SIEM devices schedule security tasksindependently because the security tasks conducted by security devicesfrom different manufacture require different parameters when scheduledand the results of the security tasks are also in different formats.Although some tasks may be logically connected and may be sequentiallyconducted to carry out a complex task, the administrator of existingSIEM devices has to schedule these tasks manually. For example, when theadministrator wants to add a new website to the network, a hostdiscovery task is scheduled to discover a newly added host. Then, theadministrator checks the result of the host discovery. If a new host isfound, a test Hypertext Transfer Protocol (HTTP) service task isscheduled to verify if an HTTP service is provided by the new host. Ifan HTTP service is found on the new host, an HTTP service scan task isconducted to verify if any leakage exists in the HTTP service. When theHTTP service is verified, then the new HTTP service may be added to thenetwork. The above mentioned host discovery task, test HTTP service taskand HTTP service scan task are scheduled manually by the administratorbecause the task may be conducted by security devices from differentmanufacturers and results of the security tasks cannot be transferred toother tasks.

In order to address the above mentioned problems, work flows and workflow templates are introduced to SIEM device 113 in various embodimentsof the present invention. The structure and functions of SIEM device113, according to one embodiment of the present invention, is describedbelow with reference to FIG. 2.

FIG. 2 illustrates exemplary functional units of an SIEM device 200 inaccordance with an embodiment of the present invention. In the presentexample, SIEM device 200 comprises a manager layer 210, an engine layer230, a device adapter layer 250 and a device layer 270. Each of theselayers represents a group of modules that conduct correspondingfunctions at different levels. SIEM device 200 further comprises a datastorage 290. Data storage 290 comprises multiple data tables, such asasset tables, vulnerability tables, original event tables, correlationevent tables, task tables, policy tables, rule tables, knowledge baseand etc. Each module of SIEM device 200 may access corresponding tablesof data storage 290 for managing corresponding data.

Manager layer 210 represents interface modules that are used formanaging the configuration and scheduling of other engines, adapters ordevices of SIEM device 200 to conduct work flows. At manager layer 210,SIEM device 200 includes an original event manager 211, a correlatedevent manager 212, an asset manager 213, a knowledge base manager 214, avulnerability manager 215, an alert policy manager 216, an action policymanager 217 and a work flow manager 218.

Original event manager 211 is used for managing original events as wellas work flow results collected from security devices that are managed bySIEM device 200. Security devices, such as WAF 271, IPS/IDS 272 andscanners 273 and 274, may collect original events while inspectingnetwork activities. These security devices may also conduct tasksscheduled by task engine 235 based on a work flow. The original eventsmay be monitored by data analytics engine 237 for any abnormal networkactivities. The original events and results of tasks may be logged andfed back to logical correlation engine 231, inventory/cross correlationengine 233 or data analytics engine 237 for further analyzing. Originalevent manager 211 may configure rules that devices at device adapterlayer 250 may use for controlling particular events and/or data thatshould be collected and how the collected data or events are to be fedback.

Correlated event manager 212 is used for defining the correlations ofthe original events collected by devices at device adapter layer 250. Insome cases, the same event may be captured and logged by multiplesecurity devices and SIEM device 200 may receive multiple originalevents for the same events. In some other cases, different events arecaptured by different security devices and these events may beassociated with the same attack. These events relating to the sameattack may be connected to form a complete attack procedure. Correlatedevent manager 212 is used for defining the rules for conducting multiplecorrelation processing, such as logical correlation, asset correlation,inventory correlation, cross correlation and knowledge correlation.

Asset manager 213 is used for managing asset attributes of networksmanaged by SIEM device 200. Asset manager 213 may create and update oneor more asset tables in data storage 290 to register all or core assetsof the network(s). Each of the assets or core assets may be assigned anasset value. A risk level of an event may be set and adjusted based onan asset value and/or other attributes of the target of the event in thenetwork. If the target of the event is a core asset of the network, thecalculated risk level of the event may result in a higher value relativeto a calculated risk level of a non-core asset. For example, a webserver providing the most important web application for a company wouldbe considered a core asset of the whole network and would typically beassigned a high asset value. When an attack is targeting this webserver, the determined risk level of this attack is high and thereforean alarm is more likely to be generated by SIEM device 200. On the otherhand, a client PC within the network would typically be considered anon-core asset of the network or may not even be present in the assetlist of the network. When an attack is targeting this client PC, thedetermined risk level is low and therefore no alarm is sent to theadministrator.

Knowledge base manager 214 is used for managing a knowledge base of datastorage 290. Knowledge base manager 214 may collect and storeinformation, including, but not limited to, services, protocol, ports,firmware, operation systems, patches, plug-ins and the like, that relateto system vulnerabilities, viruses and/or network attacks. When anattack is caught by a security device, SIEM device 200 may searchknowledge base to find corresponding vulnerabilities related to theattack at issue. If a vulnerability relating to the attack is found inknowledge base, a correlation engine may invoke inspection or scanningtools to scan a target host for the corresponding vulnerability.

Vulnerability manager 215 is used for recording vulnerabilities that areexploited by attacks in a vulnerability ID DB. Attributes of attacks,including, but not limited to, information contained within the CommonVulnerabilities and Exposures (CVE) system, BugTraq or S3CVE, may bestored in vulnerability ID DB. When a security event is received by across correlation engine, the corresponding vulnerability of thesecurity event is searched for within vulnerability ID DB. If crosscorrelation engine identifies a correlation between the attack andvulnerability based on standard attributes, it may invoke inspection orscanning tools to scan the target host for the correspondingvulnerability.

Alert policy manager 216 is used for managing the policies that regulatealarm actions when security events are received. Usually, theprivate/internal networks managed by SIEM device 200 may deploy multiplesecurity devices at different locations. These security devices may scanthe networking devices of the private/internal networks and manage theaccess to the network devices from/to a public/external network, such asthe Internet. These security devices may report network activities orsecurity events they captured periodically or in real time. Therefore,SIEM device 200 may receive numerous security events from the securitydevices. To avoid too many alarm messages, an administrator of SIEMdevice 200 may set alert policies so that only security events that havehigh risk levels (such as those representing an attack of a core assetof the network) may trigger an alarm message. Alert policies may furtherconfigure persons, time periods, types of warnings that alarm messagesmay send based on risk levels of security events. The types of warningsmay be a syslog sent to a remote terminal or an electronic mail (Email)or Short Message Service (SMS) message.

Action policy manager 217 is used for managing actions that SIEM device200 carries out when particular security events are received. Actionpolicy may include correlated event action policy, web attack actionpolicy, system attack action policy, virus event action policy and auditevent action policy. These policies may define tasks or work flows thatshould be carried out when corresponding events are received by SIEMdevice 200.

Work flow manager 218 is used for configuring work flows that can beexecuted by SIEM device 200 to carry out complex tasks. A work flowdefines a work flow task that contains a group of tasks that may besequentially or concurrently conducted by one or more security devicesso that a complex function may be accomplished automatically by SIEMdevice 200. The results of a previous task in the work flow may be usedto trigger the next task and the results may be transferred asparameters to the next task. Work flow manager 218 may create a workflow by specifying a series of commands/instructions that are carriedout by multiple security devices. Each one in the series ofcommands/instructions designates a specific task, a host that conductsthe specific task and optional parameters needed to conduct the task.The parameters may be the results of previous tasks in the work flow.The parameters may also include logic conditions for triggering thetask. By defining a work flow, SIEM device 200 may link multiplesecurity tasks together to accomplish a complex task automatically eventhough these tasks may be conducted by different security devicespotentially from different manufacturers. Each of the work flows createdby work flow manager 218 may be saved in a configuration file. A graphicrepresentation may also be used to show the procedure of a work flow sothat a user may understand the work flow task more easily. Work flowmanager 218 may further configure one or more work flow policies todefine the periods that one or more work flows or work flow templatesshould be executed. The work flow policies may also define one or moresecurity events that may trigger the execution of one or more work flowsor work flow templates. A work flow or work flow template may be startedby task scheduling engine 234 at a designated time or triggered by asecurity event based on the corresponding work flow policy.

In some embodiments, a specific work flow is used for particularsecurity devices to carry out a designated work flow task. The commandsand/or parameters for scheduling tasks in the work flow are dedicated tothe hosts conducting the task. SIEM device 200 uses specific work flowsfor each security device that are relatively simple to implement.However, specific work flows are not flexible in some scenarios. Forexample, when different security devices are conducting the same workflow task, multiple or duplicated work flows are created for thedifferent security devices. Further, when a new host is added to thenetwork, new work flows are created for the new host to carry out workflow tasks. Similarly, when an existing host is upgraded/changed, thecommands or parameters needed for conducting a task may be changed. Allthe work flows relating to the changed host should be changed in orderto correctly carry out the tasks.

In order to adapt to different network environments, in someembodiments, work flow manager 218 may also be used for configuring workflow templates that can be conducted by SIEM device 200. A work flowtemplate defines a general work flow task that contains a group ofabstract tasks describing functions needed to be conducted by multiplesecurity devices so that a complex function may be accomplishedautomatically. A work flow template does not designate the specifictasks or specific hosts that should be scheduled to conduct tasks whenthe work flow template is created. A work flow template may usedescriptors to define abstract tasks to be executed in the work flow.Descriptors may define the name, parameters and logical conditions of anabstract task without designating specific tasks or specific hosts forexecuting the tasks. At the time a work flow template is scheduled to beexecuted, a device engine may be used for translating the descriptors ofan abstract task into specific commands, parameters and logicalconditions that are used by the specific hosts for conducting theabstract tasks. In this manner, a work flow instance may be derived fromthe work flow template by the device engine. A work flow instance mayalso be conducted by the hosts in the same manner as a specific workflow created directly for the host.

Since a work flow instance is derived from a work flow template by adevice engine when or before the work flow template is scheduled tostart, it does not need to create the same work flow multiple times forsecurity devices that are desired to conduct the same work flow task.When a security device is added to carry out an existing work flow, itdoes not need to add a new work flow for the new security device.Rather, a set of commands and parameters for the newly added device maybe added to the device engine and a work flow instance for the newlyadded security device may be derived from the work flow template whenneeded. Similarly, when an existing security device is upgraded/changed,device engine 236 registers the changed commands and parameters for theexisting security device and it does not need to change any work flowtemplate.

Engine layer 230 represents multiple engines of SIEM device 200, whereineach engine drives the execution of work flows or analysis of theresults of work flows. In the present example, at engine layer 230, SIEMdevice 200 comprise a logical correlation engine 231, an assetcorrelation engine 232, an inventory/cross correlation engine 233, atask scheduling engine 234, a task engine 235, a device engine 236 and adata analytics engine 237.

Logical correlation engine 231 is used for conducting logicalcorrelation to the original events so that related or repeated eventsmay be combined into one security event. Original events may be capturedby different security devices at different locations, different networksegments and different network layers. In some cases, the same event maybe captured and logged by multiple security devices and SIEM device 200may receive multiple original events for the same event. In some othercases, different events are captured by different security devices andthese events may be associated with the same attack. These eventsrelating to the same attack may be connected to form a complete attackprocedure. After logical correlation, one security event may beextracted from the repeated or related original events and others eventsmay be discarded. Alternatively, instead of extracting one event fromrepeated or related events, a new security event may be generated torepresent the repeated or related original events.

Asset correlation engine 232 is used for conducting asset correlationamong the security events and the assets of a network so that onlysecurity events relating to core network assets will generatenotifications to the administrator of the network or trigger a workflow. To conduct the asset correlation, asset table may be setup toregister all or a subset of assets (e.g., core assets) of the network.In one embodiment, each asset is provided with an asset valuerepresenting the importance of the asset to the network. When a coreasset that has a high asset value is under attack, a high risk level isassociated with the security event and an alarm is more likely to begenerated to warn the administrator or trigger a work flow to conduct avirus/vulnerability scan of the network.

Inventory/cross correlation engine 233 may further adjust the risk levelof the security event based on whether a vulnerability that an attack istargeting exists in the target host. SIEM device 200 may maintain aninventory table that registers the attributes of assets of the network.When an attack needs a particular network environment while the targetof the attack is running in that network environment, it means that theattack may affect the target and Inventory/cross correlation engine 233may adjust the risk level of the attack. Inventory/cross correlationengine 233 may further adjust the risk level of an attack based onwhether a vulnerability that an attack is targeting exists in the targethost based on the vulnerability ID DB or knowledge base. Logicalcorrelation engine 231, asset correlation engine 232 and inventory/crosscorrelation engine 233 are described in a copending application that isassigned to the same assignee as the present application. The relatedcopending application is U.S. patent application Ser. No. 14/052,713,filed on Oct. 12, 2013 and is hereby incorporated by reference in itsentirety for all purposes.

Task scheduling engine 234 is used for launching work flows at the timesdesignated by the work flow policies. When a work flow is to belaunched/triggered, tasks in work flows or work flow templates areextracted by task scheduling engine 234. Then, the extracted tasks aresent to task engine 235 for execution. In some embodiments, after a taskin a work flow is executed by task engine 235, the results of the taskare fed back to task scheduling engine 234. Then, task scheduling engine234 may determine if the results of the task may trigger a next taskbased on one or more logical conditions defined in the work flow. Upon adetermination that the next task should be triggered, the next task issent to task engine 235 for execution.

Task engine 235 is used for driving the execution of tasks andcollecting results of tasks after tasks are executed. When a task of awork flow is received from task scheduling engine 234, task engine 235connects to the host designated in the task through a correspondingadapter and ports. The task is then executed by the specific host andthe results of the task are fed back to the task engine 235 through theadapter and ports. When an abstract task from a work flow template isreceived from task scheduling engine 234, task engine 235 sends theabstract task to device engine 236 for translation. After a specifictask translated by device engine 236 is received by task engine 235, thespecific task is executed as described above.

In some embodiments, device engine 236 is used for translating anabstract task into a specific task that can be executed by task engine235. Device engine 236 may comprise a function table that registersfunctions or tasks that security devices of SIEM device 200 can execute.The function table may comprise descriptors of tasks and correspondingspecific commands/instructions, parameters for executing the tasks ofsecurity devices. When an abstract task is received, device engine 236extracts the descriptors from the abstract task and searches thefunction table for the descriptors. Then, the descriptors of theabstract task are replaced with specific commands/instructions andparameters of a specific security device so that a specific task iscreated for execution by the specific security device. The createdspecific task is fed back to task engine 235 by device engine 236. Inother embodiments, device engine 236 may derive a work flow instancefrom a work flow template by translating the abstract tasks in the workflow template into specific tasks that may be executed by specifichosts.

Data analytics engine 237 is used for analyzing results of a work flowso that a report or an alarm message may be sent out to theadministrator based on alert policies. Data analytics engine 237 mayfurther invoke logical correlation engine 231, asset correlation engine232 and Inventory/cross correlation engine 233 to conduct correlationanalyzing to the results of a work flow so that results of the work flowthat relate to core network assets may be found and reported to theadministrator.

Device adapter layer 250 represents interfacing modules that connectSIEM device 200 and security devices of the network managed by SIEMdevice 200 for collecting security events from the security devices. Thesecurity devices of a large network may be from different manufacturersand may be deployed at various locations. The security devices may havedifferent commands/instructions for remotely calling the tasks. Securityevent reports and the results of tasks from different security devicesmay have different formats. Therefore, the adapters allow SIEM device200 to schedule different security devices to conduct designated tasksand receive security events and results of tasks in uniform formats. Inone embodiment, at device adapter layer 250, SIEM device 200 includesdistributed collectors 251 and remote task adapters 256. Distributedcollectors 251 represent multiple security event collectors, such ascollectors 253 and 255. Collectors 253 and 255 are used for collectingoriginal security events from security devices. These original securityevents from different security devices may contain different contents indifferent formats. The original security events may be sent tonormalization 252 and 254 for normalizing. After normalization, theinformation that is useful for correlation in the original securityevents may be retained and saved in a unified format. It will be easierfor correlation engines to correlate events from different sources afterthe original events are normalized.

Remote task adapters 256 represent interfacing modules that connectingSIEM device 200 and security devices of the network managed by SIEMdevice 200 for executing tasks by the security devices and receivingfeedback/results of the tasks from the security devices. In someembodiments, SIEM device 200 may include multiple scan adapters, such asscan adapter 257 and 258. In the present example, scan adapters 257 and258 further comprises four interfaces for carrying out differentscanning tasks, such as a system scan, a web scan, a port scan and ahost scan. Those of ordinary skill in the art will appreciate thatvarious other kinds of adapters may be used for connecting othersecurity devices and for executing other tasks.

Device layer 270 represents security devices that are integrated with orconnected to SIEM device 200. The security devices may conduct varioustasks that may be scheduled locally or remotely by SIEM device 200 basedon a work flow or a work flow template. In the present example, deviceadapter layer 250 includes a WAF 271, an IPS/IDS 272, a vulnerabilityscanner 273 and a vulnerability scanner 274. These security devices maybe from different manufacturers and may have differentcommands/instructions to be scheduled for executing tasks. Thesesecurity devices may also report security events, task results/scanresults back to SIEM device 200. Those of ordinary skill in the art willappreciate that security devices other than those described withreference to device adapter layer 250 may be integrated with orconnected to SIEM device 200. Because the functions and operations ofthese security devices are well known in the art, detailed descriptionsthereof will be omitted.

FIG. 3 is a flow diagram illustrating the general steps of a method forconducting a work flow by an SIEM device in accordance with anembodiment of the present invention. Depending upon the particularimplementation, the various process and decision blocks described belowmay be performed by hardware components, embodied in machine-executableinstructions, which may be used to cause a general-purpose orspecial-purpose processor programmed with the instructions to performthe steps, or the steps may be performed by a combination of hardware,software, firmware and/or involvement of humanparticipation/interaction.

At block 301, a work flow template is created by the administrator of anSIEM device. The work flow template defines abstract tasks that may beconducted by multiple security devices. The abstract tasks describe thenames or functions of tasks that may be conducted by multiple securitydevices without specific commands/instructions or parameters that areneeded for conducting the tasks. Descriptors may be used for describingthe task name, parameters and logical conditions for scheduling thetasks. By using work flow templates and dynamically creating a work flowinstance when scheduled, an SIEM device has more flexibility to usevarious security devices from different manufacturers. The management ofwork flows of the SIEM device is also simplified because the work flowtemplates remain unchanged when security devices are changed or added tothe network managed by the SIEM device.

At block 302, at the time a work flow template is scheduled forexecution, a work flow instance or specific tasks are derived from thework flow template by translating the abstract tasks in the work flowtemplate into specific tasks that can be executed by specific securitydevices. A device engine of the SIEM device may maintain a task tablethat register tasks that can be called by the SIEM device. The specificcommands/instructions, parameters, logical conditions and correspondingdescriptors thereof are registered in the task table. When a work flowtemplate is scheduled to be executed by a task scheduling engine of theSIEM device, a work flow instance or specific tasks may be derived bythe device engine before it is executed.

At block 303, the work flow is schedule by the task scheduling engine.Each task defined in the work flow is read out by the task schedulingengine. The task and parameters needed for execution are sent to thecorresponding security device for execution. The tasks may besequentially or concurrently executed by multiple security devicesdespite the security devices being from different manufacturers and/orhaving different parameters or formats for conducting the tasks.

At block 304, execution results of tasks are collected by the taskscheduling engine. In some embodiments, the execution results of a taskin the work flow may be used for determining if a following task shouldbe triggered. In some other embodiments, the final results of a workflow may also be reported to the administrator. Therefore, the resultsof execution of each task of the work flow may be collected by the taskscheduling engine through the adapters and ports with the securitydevices.

At block 305, the task scheduling engine may also report the executionresults of the work flow to an administrator of the SIEM device. In oneembodiment, the execution results of a work flow may include indicationsregarding whether each of the tasks in the work flow have been executedsuccessfully. In other embodiments, the execution results of a work flowmay include all the logs of each of the tasks in the work flow. Theexecution results of the work flow may be sent to correlation engines ofthe SIEM device. The correlation engines may filter the results of thework flow and identify those of the security events that relate to coreassets of the network. When the risk levels of the security events arehigh, alarm messages, such as Emails, SMSs or syslogs, may be sent tothe administrator based on the alert policies.

FIG. 4 is a flow diagram illustrating the execution of a work flow inaccordance with an embodiment of the present invention. A work flow ofan SIEM device defines tasks that are conducted by multiple securitydevices to achieve comprehensive management of a network. A work flowmay be a set of commands/instructions that can be carried out bysecurity devices together with parameters or logical conditions for theexecution of commands/instructions. A work flow may be created directlyby an administrator of the SIEM device. FIG. 4 illustrates the executionof a work flow after it is created.

At block 401, when a work flow is started by a task scheduling engine, atask in the work flow is read out. The task scheduling engine sends thetask to task engine for execution.

At block 402, the task engine receives the task and schedules a securitydevice to execute the task. As the task includes information indicativeof the designated host (such as a host name or an Internet Protocol (IP)address) and commands and parameters for executing the task by the host,the task engine may connect to the host through an adapter between theSIEM device and the host and send the commands to the host forexecution.

At block 403, the task engine collects results of execution of the taskthrough the connection between the SIEM device and the host. The resultsof execution of the task may be an indication of whether the tasksuccessfully executed and/or a log of execution of the task.

At block 404, the task scheduling engine may check the results of thetask and determine if the next task should be triggered based on logicalconditions defined in the work flow. If the task scheduling enginedetermines that the next task should be executed, the execution resultsof the task may be transferred to the next task at block 406 and theprocess goes back to block 401 for execution of the next task in thework flow.

If the task scheduling engine determines that a further task need not beexecuted, e.g., all the tasks in the work flow are finished, results ofthe work flow is reported to the administrator of the network at block405. The results of work flow may indicate whether each of the tasks inthe work flow have been executed successfully. The results of work flowmay also include all the logs of executions of each task in the workflow.

FIG. 5 is a flow diagram illustrating scheduling tasks based on a workflow template in accordance with an embodiment of the present invention.In the present example, a work flow template is scheduled by taskscheduling engine instead of a specific work flow as shown in FIG. 4 andtasks in the work flow template are derived when the work flow templateis scheduled.

At block 501, when a work flow template is scheduled based on a workflow policy or is triggered by a security event based on an actionpolicy, task scheduling engine retrieve an abstract task from the workflow template. The abstract task may comprise descriptors of the taskthat a security device is to execute.

At block 502, the task scheduling engine sends the abstract taskextracted from the work flow template to a device engine. The deviceengine may extract the descriptors from the abstract task and search atask table for actual parameters, such as commands/instructions, thatcorrespond to the descriptors of the abstract task. The device enginethen replaces the descriptors of abstract tasks with the correspondingactual parameters of specific hosts and creates actual tasks that can beexecuted by the hosts. The actual task derived from the abstract task isthen transferred back to the task scheduling engine for execution.

At block 503, the task scheduling engine receives the actual taskderived from the abstract task. The actual task contains the host,commands/instructions and necessary parameters for executing the task.

Blocks 504 through 508 generally correspond to blocks 402 through 406 ofFIG. 4 and hence further description thereof is omitted for brevity.

FIG. 6 is a flow diagram illustrating scheduling tasks based on a workflow template in accordance with another embodiment of the presentinvention. In the present example, a work flow template is scheduled bytask scheduling engine instead of a specific work flow as shown in FIG.4 and a work flow instance is derived from the work flow template whenthe work flow template is scheduled.

At block 601, a work flow template is scheduled based on a work flowpolicy or is triggered by a security event based on an action policy.

At block 602, the task scheduling engine sends the work flow template toa device engine. The work flow template may contain multiple abstracttasks. The device engine may retrieve each abstract task from the workflow template and extract the descriptors from the abstract task. Thedevice engine searches a task table for actual parameters thatcorresponding to the descriptors of the abstract tasks. The deviceengine then replaces the descriptors of the abstract tasks with thecorresponding actual parameters of a specific host and creates a workflow instance that can be executed by the host. The work flow instancederived from the work flow template is transferred back to the taskscheduling engine for execution.

Blocks 603 through 608 generally correspond to blocks 401 through 406 ofFIG. 4 and hence further description thereof is omitted for brevity.

FIG. 7 is a flow diagram illustrating a website discovery work flow inaccordance with an embodiment of the present invention. In the presentexample, a website discovery work flow comprises three tasks, i.e., aservice discovery task, an HTTP service test task and a website scantask, each of which may be carried out by different scanners. Thewebsite discovery work flow may be used for discovering a website thatis newly added to the network and verifying if any vulnerability existsin the website before the website is allowed to provide service. Anexemplary graphic representation of the website discovery work flow ofthe present example is shown in FIG. 8.

At block 701, a website discovery work flow is started by a taskscheduling engine of an SIEM device.

At block 702, a first task, i.e., a service discovery task, is retrievedfrom the website discovery work flow. The service discovery taskcontains an IP address or a network segment that is to be scanned. TheSIEM device then schedules a service scanner to scan the designated IPaddress or network segment in order to find any new website.

At block 703, the SIEM device may check the log of the service scannerto determine if any host discovered by the service scanner is notregistered in the network asset table. If a host is discovered and wasnot previously registered in the network asset table, the procedure goesto block 704. If no new host is discovered by the service scanner, thework flow is finished.

At block 704, a second task, i.e., an HTTP service test task, isretrieved from the work flow and an HTTP service scanner is scheduled bythe SIEM device to detect the IP address of newly added host for HTTPservice. The ports that are used for providing the HTTP service of thenew host are tested by the HTTP service scanner to determine if thenewly added host is providing HTTP service. The HTTP service scanner mayalso test if a website is already created at the host.

At block 705, the result of HTTP service scan task is examined. If thenew host does not provide HTTP service or no website is created, thework flow is finished. If the new host is providing HTTP service and anew website is already created, the procedure goes to next step andfurther scanning will be carried out.

At block 706, a third task, i.e., a website scanning task, is retrievedfrom the work flow. The SIEM device schedule a website scanner to detectthe newly added website to find out any vulnerability exists in thewebsite.

At block 707, the SIEM device allows or blocks the new website based onthe results of website scan. The result of website discovery work flowmay also be reported to the administrator of the SIEM device.

In the above example, the website discovery work flow is scheduledmanually or periodically. In other embodiments, the website discoverywork flow may be triggered by a network audit event. After a networkhardware auditing, a new host is found and then the website discoverywork flow may be started to scan the new host for HTTP service andvulnerabilities. By using a website discovery work flow, the managementof new websites in a network is simplified and may be conductedautomatically.

In some embodiments, a web scanning task and a website block task may becombined to form a web scanning work flow. The web scanning work flowmay be conducted manually or periodically. Further, in one embodiment ofthe present invention, a work flow may include another work flow to forma complex work flow. For example, a website discovery work flow mayinclude a service discovery task, an HTTP service test task and awebsite scan work flow.

FIG. 9 is a flow diagram illustrating a closed-loop work flow for asecurity event in accordance with an embodiment of the presentinvention. A closed-loop work flow is a work-flow-based integratedprocedure that may be carried out by an SIEM device when attacks arecaptured. By defining various closed-loop work flows for variousattacks, the processing of every attack becomes an integrated procedurestarting from event capturing to leakage repair so that each processingof attacks can be carried out timely and accurately.

In the following description, an example of closed-loop work flow isdescribed based on a scenario in which a security event received by theSIEM device is a SQL injection attack. Those skilled in the art willappreciate that other security events may also be processed by the sametype of closed-loop work flow.

At block 901, a closed-loop work flow begins with a task of collectingone or more security events by the SIEM device from different securitydevices that are distributed at different locations. The security eventsmay be security logs that may be sent to the SIEM device in real time orperiodically. The security logs may contain the most importantinformation regarding the events, including, but not limited to, thesource IP addresses, the destination IP addresses, protocols, ports,applications, times of the events and the like. The security logs arethen filtered and normalized so that relevant information that is usefulfor further analysis may be kept and all the information may be storedin a uniform format even the security logs are recorded by securitydevices from different manufacturers. In the present embodiment, a webapplication firewall of the network detects a SQL injection attack. Theweb application firewall first blocks the attack and sends a syslog toan event collector of the SIEM device.

At block 902, a correlation analyzing task of the closed-loop work flowis triggered by the security events. The correlation analyzing taskconducts one or more of logical correlation analysis, asset correlationanalysis, and inventory correlation analysis to the received securityevents. By logical correlation analysis, multiple security events thatcorrespond to the same attack may be simplified to one security event.By asset correlation analysis, security events that are targeting coreassets of a network are extracted. Inventory correlation analysis may beused for further verifying if the target of an attack possesses theenvironment or leakage that is necessary for the attack to succeed.After these correlation analyses, a risk level may be given to eachsecurity event.

At block 903, a leakage verification task of the closed-loop work flowis triggered by the SQL injection attack because the risk level of theattack is higher than a threshold. The SIEM device schedules a webapplication scanner to scan the target host of the SQL attack to verifyif a leakage does exist in the target host. In the present example, theweb application scanner finds a SQL injection leakage does exist in aweb page of the host. The scanner may also find out the commonvulnerabilities and exposures (CVE) attribute, a BugTraq attribute or anS3CVE attribute of the attack.

At block 904, a risk warning is sent out to an administrator of the SIEMdevice based on predetermined alert policies. The risk warning may be asyslog sent to a remote terminal or an electronic mail (Email) or ShortMessage Service (SMS) message sent to the administrator.

At block 905, an emergency response task in the closed-loop work flow isstarted by the SIEM device. The emergency response may includetemporarily blocking accesses to the page with the leakage, stopping webservice on the host and/or block the access to the host. It will beappreciated by those skilled in the art that other emergency responsesmay be used for other applications.

At block 906, a leakage repairing task of the closed-loop work flow isstarted. The leakage repairing task may send out a work order to asoftware engineer indicating the leakage that needed to be repaired. Theleakage repairing task may also monitor the repairing work until therepairing work is finished.

FIG. 10 is an example of a computer system 1000 with which embodimentsof the present disclosure may be utilized. Computer system 1000 mayrepresent or form a part of a network appliance (e.g., firewall 112 orSIEM device 113), a server or a client workstation.

Embodiments of the present disclosure include various steps, which willbe described in more detail below. A variety of these steps may beperformed by hardware components or may be tangibly embodied on acomputer-readable storage medium in the form of machine-executableinstructions, which may be used to cause a general-purpose orspecial-purpose processor programmed with instructions to perform thesesteps. Alternatively, the steps may be performed by a combination ofhardware, software, and/or firmware.

As shown, computer system 1000 includes a bus 1030, a processor 1005,communication port 1010, a main memory 1015, a removable storage media1040, a read only memory 1020 and a mass storage 1025. A person skilledin the art will appreciate that computer system 1000 may include morethan one processor and communication ports.

Examples of processor 1005 include, but are not limited to, an Intel®Itanium® or Itanium 2 processor(s), or AMD® Opteron® or Athlon MP®processor(s), Motorola® lines of processors, FortiSOC™ system on a chipprocessors or other future processors. Processor 1005 may includevarious modules associated with units as described in FIG. 2.

Communication port 1010 can be any of an RS-232 port for use with amodem based dialup connection, a 10/100 Ethernet port, a Gigabit or 10Gigabit port using copper or fiber, a serial port, a parallel port, orother existing or future ports. Communication port 1010 may be chosendepending on a network, such a Local Area Network (LAN), Wide AreaNetwork (WAN), or any network to which computer system 1000 connects.

Memory 1015 can be Random Access Memory (RAM), or any other dynamicstorage device commonly known in the art. Read only memory 1020 can beany static storage device(s) such as, but not limited to, a ProgrammableRead Only Memory (PROM) chips for storing static information such asstart-up or BIOS instructions for processor 1005.

Mass storage 1025 may be any current or future mass storage solution,which can be used to store information and/or instructions. Exemplarymass storage solutions include, but are not limited to, ParallelAdvanced Technology Attachment (PATA) or Serial Advanced TechnologyAttachment (SATA) hard disk drives or solid-state drives (internal orexternal, e.g., having Universal Serial Bus (USB) and/or Firewireinterfaces), such as those available from Seagate (e.g., the SeagateBarracuda 7200 family) or Hitachi (e.g., the Hitachi Deskstar 7K1000),one or more optical discs, Redundant Array of Independent Disks (RAID)storage, such as an array of disks (e.g., SATA arrays), available fromvarious vendors including Dot Hill Systems Corp., LaCie, NexsanTechnologies, Inc. and Enhance Technology, Inc.

Bus 1030 communicatively couples processor(s) 1005 with the othermemory, storage and communication blocks. Bus 1030 can be, such as aPeripheral Component Interconnect (PCI)/PCI Extended (PCI-X) bus, SmallComputer System Interface (SCSI), USB or the like, for connectingexpansion cards, drives and other subsystems as well as other buses,such a front side bus (FSB), which connects processor 1005 to systemmemory.

Optionally, operator and administrative interfaces, such as a display,keyboard, and a cursor control device, may also be coupled to bus 1030to support direct operator interaction with computer system 1000. Otheroperator and administrative interfaces can be provided through networkconnections connected through communication port 1010.

Removable storage media 1040 can be any kind of external hard-drives,floppy drives, IOMEGA® ZIP Drives, Compact Disc-Read Only Memory(CD-ROM), Compact Disc-Re-Writable (CD-RW), Digital Video Disk-Read OnlyMemory (DVD-ROM).

Components described above are meant only to exemplify variouspossibilities. In no way should the aforementioned exemplary computersystem limit the scope of the present disclosure.

While embodiments of the invention have been illustrated and described,it will be clear that the invention is not limited to these embodimentsonly. Numerous modifications, changes, variations, substitutions, andequivalents will be apparent to those skilled in the art, withoutdeparting from the spirit and scope of the invention, as described inthe claims.

What is claimed is:
 1. A method comprising: creating, by a securityinformation and event management (SIEM) device, a work flow, said workflow including a plurality of security tasks that are to be performed byone or more security devices; starting the work flow by scheduling theplurality of security tasks defined in the work flow; and collecting, bythe SIEM device, results of the plurality of security tasks after theyare performed by the one or more security devices.
 2. The method ofclaim 1, further comprising: creating a work flow template that definesa complex function and a plurality of abstract security tasks that areneeded for performing the complex function; and deriving a work flowinstance for a security device of the one or more security devices thatis designated to conduct the work flow from the work flow template. 3.The method of claim 2, wherein said deriving a work flow instance for asecurity device of the one or more security devices that is designatedto conduct the work flow from the work flow template further comprisessetting up parameters of the plurality of security tasks of the workflow instance.
 4. The method of claim 1, wherein the plurality ofsecurity tasks of the work flow are performed serially.
 5. The method ofclaim 4, further comprising determining if a security task of theplurality of security tasks in the work flow should be performed basedon the results of one or more previous security tasks of the pluralityof security tasks of the work flow.
 6. The method of claim 4, furthercomprising transferring results of one or more previous security tasksof the plurality of security tasks of the work flow to a next securitytask of the plurality of security tasks of the work flow.
 7. The methodof claim 1, wherein the plurality of security tasks of the work flow areperformed in parallel.
 8. The method of claim 1, wherein saidcollecting, by the SIEM device, results of the plurality of securitytasks further comprises normalizing the results.
 9. The method of claim1, further comprising: performing asset correlation to the results ofthe plurality of security tasks; reporting the results of the pluralityof security tasks if they are correlated to core network assets.
 10. Themethod of claim 1, further comprising reporting the results of theplurality of security tasks based on an alert policy.
 11. The method ofclaim 1, wherein the work flow comprises a website automatic discoverywork flow and the plurality of security tasks comprise a servicediscovery, a test Hypertext Transfer Protocol (HTTP) service and awebsite scan.
 12. The method of claim 1, wherein said work flowcomprises a website scan work flow and the plurality of security taskscomprise website scanning and web application firewall blocking.
 13. Themethod of claim 1, wherein the work flow comprises a closed-loopsecurity event processing work flow and the closed-loop security eventprocessing work flow comprises event collecting, leakage verificationand emergency response processing.
 14. The method of claim 13, whereinthe closed-loop security event processing work flow further comprisescorrelation analyzing, risk warning and leakage repair.
 15. A computersystem comprising: non-transitory storage device having tangiblyembodied therein instructions representing a security application; andone or more processors coupled to the non-transitory storage device andoperable to execute the security application to perform a methodcomprising: creating a work flow, said work flow including a pluralityof security tasks that are to be performed by one or more securitydevices; starting the work flow by scheduling the plurality of securitytasks defined in the work flow; and collecting results of the pluralityof security tasks after they are performed by the one or more securitydevices.
 16. The computer system of claim 15, wherein the method furthercomprises: creating a work flow template that defines a complex functionand a plurality of abstract security tasks that are needed forperforming the complex function; and deriving a work flow instance for asecurity device of the one or more security devices that is designatedto conduct the work flow from the work flow template.
 17. The computersystem of claim 16, wherein said deriving a work flow instance for asecurity device of the one or more security devices that is designatedto conduct the work flow from the work flow template further comprisessetting up parameters of the plurality of security tasks of the workflow instance.
 18. The computer system of claim 15, wherein theplurality of security tasks of the work flow are performed serially. 19.The computer system of claim 18, wherein the method further comprisesdetermining if a security task of the plurality of security tasks in thework flow should be performed based on the results of one or moreprevious security tasks of the plurality of security tasks of the workflow.
 20. The computer system of claim 18, wherein the method furthercomprises transferring results of one or more previous security tasks ofthe plurality of security tasks of the work flow to a next security taskof the plurality of security tasks of the work flow.
 21. The computersystem of claim 15, wherein the plurality of security tasks of the workflow are performed in parallel.
 22. The computer system of claim 15,wherein said collecting results of the plurality of security tasksfurther comprises normalizing the results.
 23. The computer system ofclaim 15, wherein the method further comprises: performing assetcorrelation to the results of the plurality of security tasks; reportingthe results of the plurality of security tasks if they are correlated tocore network assets.
 24. The computer system of claim 15, wherein themethod further comprises reporting the results of the plurality ofsecurity tasks based on an alert policy.
 25. The computer system ofclaim 15, wherein the work flow comprises a website automatic discoverywork flow and the plurality of security tasks comprise a servicediscovery, a test Hypertext Transfer Protocol (HTTP) service and awebsite scan.
 26. The computer system of claim 15, wherein said workflow comprises a website scan work flow and the plurality of securitytasks comprise website scanning and web application firewall blocking.27. The computer system of claim 15, wherein the work flow comprises aclosed-loop security event processing work flow and the closed-loopsecurity event processing work flow comprises event collecting, leakageverification and emergency response processing.
 28. The computer systemof claim 27, wherein the closed-loop security event processing work flowfurther comprises correlation analyzing, risk warning and leakagerepair.